Connective Tissues Flashcards
What is the main functions of Connective Tissues
1) It binds, supports and strengthens other body tissues.
- A major transport system of the body (blood is a connective tissue).
- A major site of stored energy reserves (fat or adipose tissue is a
connective tissue).
Features of Connective Tissues; LIKE epithelia
CT is supplied by nerves
– (Exception: cartilage)
Features of Connective Tissues; UNLIKE epithelia
CT is NOT found on body surfaces
– (Think of where bones, cartilage, blood are located…)
- CT can be highly vascular
– (Exceptions: cartilage which is avascular and tendons with very
little blood supply)
Connective tissue (CT) is composed of…?
EXTRACELLULAR MATRIX (ECM) and CELLS
(CT = ECM + Cells)
What is the ECM is composed of?
1)Ground Substance (GS) in association with
2) Protein Fibres (3 major types in different proportions)
(ECM= GS + Fibres)
The protein fibres of the ECM are secreted by …?
the cells in
the ECM/CT
The structure of the ECM largely dictates the connective
tissue qualities, what are two examples of this?
Cartilage: ECM is firm and rubbery
Bone: ECM hard and inflexible.
What is ground substance composed of?
Water
* Proteins (gelatin in jelly!)
* Polysaccharides (sugars-Glycosaminoglycans (GAGS or
mucopolysaccharides)
(GS = H 2 O + proteins+ polysaccharides)
(GAGS) Glycosaminoglycans joins with core proteins to form…?
proteoglycans
(Proteoglycans: Core Protein + Glycosaminoglycan (GAG))
What is another name for Glycosaminoglycans (GAGS) & what is its structure?
Other name “mucopolysaccharides”
– They are long unbranched polysaccharides”
What are 4 Sulphated Glycosaminoglycans (GAGS)?
- Dermatan sulphate
- Heparin sulphate
- Keratan sulphate
- Chondroitin sulphate
-These bind to core proteins to form proteoglycans
What are Non-Sulphated Glycosaminoglycans (GAGS)?
-Hyaluronic acid
Hyaluronic acid does not bind directly to core protein backbone but is joined to various proteoglycans
(no protein core)
The glycosaminoglycan hyaluronic acid is unusual in that it is not sulphated or covalently bound to a core protein.
Highly polar and attract water so collectively, the glycosaminoglycans trap water to make the ground
substance more jelly-like.
(GAGS) Hyaluronic acid application?
Hyaluronic Acid: viscous slippery substance binds cells together.
Lubricates joints and maintains shape of eyeball
Hyaluronidase: how is it produced and its function?
produced by white blood cells, sperm and some bacteria.
This makes ground substance more liquid so they
can move more easily in it or makes access to the
egg easier for sperm.
Chondroitin Sulphate application?
supports and provides the adhesive
features of cartilage, bone, skin, blood vessels
Keratan Sulphate application?
found in bone, cartilage, cornea of the eye
Dermatan Sulphate application?
found in skin, tendons, blood vessels,
heart valves
Abnormal Periorbital ECM and
thyroid disease (Exopthalmos) info?
Most common in younger women
* Goitre (swollen thyroid gland)
* Autoimmune over-activation of thyroid (goitre)
* Autoimmune action on fibroblasts in ECM of eye (exophthalmos)
The deposition of glycosaminoglycans and the influx of
water increase the orbital contents
Can you sometimes get abnormal ECM ground substance?
Yes
How many different types of connective tissue fibres are there in the extracellular matrix (ECM) & what are they?
3
Collagen Fibres
Reticular Fibres
Elastic Fibres
Collagen Fibres features?
(thick) Very strong but flexible to resist pulling forces
- Features vary in different tissues e.g. more water around
collagen in cartilage than in bone.
what percentage does collagen make up if your body? & is it the most abundant protein?
- Collagen 25% of your body and is most abundant
protein!
Where are collagen fibres commonly found in the body?
bone, cartilages, tendons and ligaments
* Parallel bundles
What is reticular fibre composed of?
Composed of collagen with coating of glycoprotein
* Collagen in fine bundles with coating of glycoprotein
(more protein than sugar)